Detection of yeast species associated with respiratory tract infections using internal transcript spacer

Abstract

Fungal infections have increased during last two years to become a grown threat due to the prevalence of
COVID-19, which is the first factor to inhibit the immune system. Therefore, this study aimed to screen
fungal species associated with respiratory infections using internal transcript spacer as diagnostic marker.
The total samples collected in this study were 160 samples of sputum, which included filamentous fungi
and yeasts. The total number of positive samples was 124 (77.5%) which included 62 yeast positive
samples, and 62 filamentous positive samples. Yeast samples included different genera and the highest
percentage belonged to the genus Candida. Five species of the genus Candida, C. tropical. C. albicans, C.
dubliniensis, C. krusei and C. glabrata were identified based on phenotypic characteristics and biochemical
tests as well as using chromogenic Candida agar medium. The highest percentage of isolated yeasts was
Candida yeast 53, with a rate of )85.48%( out of 62 samples of yeasts.The highest percentage of yeasts was
Candida albicanis, which amounted to 26 (41.93) positive samples for examination according to the
genetic diagnosis of yeasts.